The invention relates to slicing and conveying systems for food products.
Slicing machines and associated conveyors are known that cut slices from food loaves and deposit the slices in a shingled stack or draft on a moving conveyor. Such a machine is described for example in U.S. Pat. Nos. 5,649,463; 5,704,265; 5,974,925; as well as patent publications EP0713753 and WO99/08844.
A system has been developed by Formax, Inc. of Mokena, Ill., U.S.A. wherein a rear slicing machine simultaneously slices a pair of loaves of different flavors, flavors A and C, to form two shingled drafts that are then delivered by a pass-through conveyor through a rear entrance of a front slicing machine. The front slicing machine slices a pair of loaves of different flavors, flavors B and D, to form two shingled drafts which are deposited directly on the shingled drafts of the A and C flavors that were transported to the second slicing machine by the pass-through conveyor. Thus, a pair of combined drafts of four flavors A+B and C+D is formed. The combined drafts of flavors A+B and C+D are transported to an overlap conveyor which routes the C+D draft behind the A+B draft to form an elongated combined draft of flavors A, B, C, D. The flavors A, B, C, D can be different types of meats, such as ham and bologna, or cheeses, such as American and Swiss. This elongated combined draft of flavors A, B, C, D can be packaged as a four flavor variety pack.
Although the above system incorporates two slicing machines that each slice two different flavor loaves to provide a four flavor variety pack, it is also known to provide a three flavor variety pack wherein the rear slicing machine slices two loaves, forming drafts A and C and the front slicing machine slices only one loaf, forming draft B. A two flavor combined draft A, B, formed as described above by both the rear and the front slicing machine, is combined at the overlap conveyor with the single flavor draft C, to form a three flavor elongated combined draft A, B, C.
The present inventors have recognized that the aforementioned system requires adjustments to maintain a consistent overall length of the elongated combined draft. The cause for these adjustments is in part due to product loaves that are not consistently round. Product loaves can be oval or flattened in some manner or vary in diameter from loaf to loaf. A decrease in slice length, with the spacing or slice exposure distance remaining constant will result in a decreased length of the elongated combined draft. An increase in slice length, with the spacing or slice exposure distance remaining constant will result in an increased length of the elongated combined draft.
As illustrated in FIG. 8, sixteen slices of round product spaced at 0.3 inches slice exposure distance will give a 9 inch length of the elongated combined draft. If, however, one of the product flavors becomes oval (length 4.25xc3x97width 4.75 inches) and the 0.3 inch space is maintained, then an unacceptable gap f is needed between drafts if the 9 inch overall length of the elongated combined draft is maintained. If the product is oval (length 4.25xc3x97width 4.75 inches), the 0.3 inch slice exposure distance may be adjusted to 0.317 inches and the 9 inch overall length of the elongated combined draft will be maintained. However, if the product then returns to round, and the slice exposure distance remains at 0.317 inches, if the 9 inch overall length of the elongated combined draft is maintained, then the gap f becomes too small, or the draft length becomes greater than 9 inches. Given variable loaf profiles, the system must be manually and frequently adjusted to ensure a consistent nine inch draft length and a consistent gap between drafts which make up the elongated combined draft.
The present inventors have recognized that it would be advantageous to provide a slicing and conveying system that could provide a succession of elongated combined drafts comprising drafts of different flavors and wherein each elongated combined draft had a consistent gap between flavor drafts and a consistent overall length. The present inventors have recognized that consistent gap and overall length are important in packaging and overall product appeal to consumers.
A slicing and conveying system is provided for arranging multi-flavor drafts of slices from two separate slicing machines in an elongated combined draft for packaging in a multi-flavor variety pack. The invention provides a control system for automatically controlling the overall length of the elongated combined draft, and slice and draft spacing within the combined draft.
In accordance with an exemplary embodiment of the invention, a slicing and conveying system for forming a three or more flavor combined draft includes:
a first slicing machine having a rotating slicing blade operable in an effective first cutting plane, and a loaf feed introducing a first loaf into the first cutting plane to form a succession of first slices;
a first output conveyor beneath the first slicing machine for receiving the first slices in a first draft;
a second slicing machine having a rotating slicing a blade operable in an effective second cuffing plane, and a loaf feed introducing a second loaf into the second cutting plane to form a succession of second slices;
a second output conveyor beneath the second slicing machine for receiving the second slices in a second draft;
a pass-through conveyor receiving the first draft from the first output conveyor and transferring the first draft to the second output conveyor, wherein the second draft is added to the first draft to form a first combined draft;
wherein one of the first and second slicing machines comprises a third loaf feed for introducing a third loaf into one of the first and second cutting planes to form a succession of third slices in a third draft; and
an overlap conveyor arranged downstream of the second output conveyor, wherein the first combined draft is transferred onto the overlap conveyor and combined with the third draft on the overlap conveyor to form an elongated combined draft;
a first length sensor for determining a length of the first draft from the first slicing machine;
a second length sensor for determining a length of the second draft from the second slicing machine;
a third length sensor for determining a length of the third draft; and
a control receiving input from the first, second, and third length sensors and outputting a control signal to said first and second output conveyors to adjust the spacing of the slices within the first, second and third drafts to control the length of the elongated combined draft.
As a further aspect of the exemplary embodiment of the invention, a combined length sensor can be provided for sensing a length of the elongated combined draft. The combined length sensor can be signal-connected to the control, and the control can be signal-connected to at least one of the conveyors of the overlap conveyor to adjust the spacing of the drafts which are merged on the overlap conveyor, to adjust the overall length of the elongated combined draft.
As a further exemplary aspect of the invention, the first slicing machine comprises the third loaf feed for introducing the third loaf into the first cutting plane, adjacent the first loaf, to form the succession of third slices in the third draft. The second slicing machine comprises a fourth loaf feed for introducing a fourth loaf into the second cutting plane adjacent the second loaf to form a succession of fourth slices in a fourth draft. The third draft is transferred by the pass-through conveyor onto the second output conveyor of the second slicing machine, wherein the fourth draft is added to the third draft to form a second combined draft. An overlap conveyor is arranged downstream of the second output conveyor, wherein the first and second combined drafts are transferred onto the overlap conveyor to form a four-draft elongated combined draft.
According to this exemplary embodiment of the invention, a fourth length sensor is provided for sensing a length of the fourth draft. The control receives input from the first, second, third, fourth and combined length sensors and outputs control signals to the first and second output conveyors, and the overlap conveyor to control the length of, and slice and draft spacing within, the elongated combined draft.
An exemplary method of the invention controls the length of an elongated combined draft of food slices cut by a plurality of slicing machines, and comprises the steps of:
providing a first slicing machine having a rotating slicing blade operable in an effective first cutting plane, and a loaf feed introducing a first loaf into the first cutting plane to form a succession of first slices;
providing a first output conveyor beneath the first slicing machine for receiving the first slices in a first draft;
providing a second slicing machine having a rotating slicing blade operable in an effective second cutting plane, and a loaf feed introducing a second loaf into the second cutting plane to form a succession of second slices;
providing a second output conveyor beneath the second slicing machine for receiving the second slices in a second draft;
providing a pass-through conveyor receiving the first draft from the first output conveyor and transferring the first draft to the second output conveyor, wherein the second draft is added to the first draft to form a first combined draft;
providing that one of the first and second slicing machines comprises a third loaf feed for introducing a third loaf into one of the first and second cutting planes to form a succession of third slices in a third draft;
providing an overlap conveyor arranged downstream of the second output conveyor, the overlap conveyor having merging paths, wherein the first combined draft is transferred onto the overlap conveyor and merged with the third draft on the overlap conveyor to form an elongated combined draft;
sensing a length of the first draft from the first slicing machine;
sensing a length of the second draft from the second slicing machine;
sensing a length of the third draft; and
automatically adjusting the speed of at least one of the output conveyors to adjust the length of one of the first, second or third drafts to adjust the length of a succeeding elongated combined draft.
A further aspect of the method comprises the further step of automatically adjusting the relative speed of a crossover conveyor of the overlap conveyor to adjust the length of the elongated combined draft.
A still further aspect of the method comprises the further step of sensing the length of the elongated combined draft and adjusting the speed of at least one of the output conveyors.
A still further aspect of the method comprises the further step of sensing the length of the elongated combined draft and adjusting the relative speed of a crossover conveyor of the overlap conveyor to adjust the length of the elongated combined draft.
A still further aspect of the method comprises the further step of sensing the length of the elongated combined draft and adjusting the relative speed of a crossover conveyor of the overlap conveyor and the speed of at least one of the output conveyors to adjust the length of the elongated combined draft.
According to another aspect of the invention, a slicing and conveying system is provided for arranging slices from a slicing machine in a shingled draft of controlled length. This aspect can be applicable to a single slicing machine or multiple in-line slicing machines as described above. Particularly, a control system is provided for sensing the length of the draft and automatically adjusting the degree of shingling of the slices in a subsequent shingled draft by controlling the speed of an output conveyor which receives the slices from the slicing machine.
According to an exemplary embodiment, a slicing machine having a rotating slicing blade is operable in an effective cutting plane, and a loaf feed introduces a loaf into the cutting plane to form a succession of slices. An output conveyor located beneath the slicing machine receives the slices, the output conveyor movable to create a shingled draft of the slices. A length sensor determines a length of the draft. A control receives input from the length sensor and outputs a control signal to the output conveyor to control the length of the draft.
The output conveyor can comprise a conveying surface circulated by a servomotor and a servomotor drive, the servomotor drive controls the servomotor. The servomotor drive is signal-connected to the control, the control operable to adjust the speed of the conveying surface.
The length sensor can comprise an optical detector arranged above the conveying surface which senses the beginning and end of the draft passing by the optical sensor on the conveying surface. The output conveyor comprises a speed signal output that is signal-connected to the control. The control comprises a timer, and the timer times the duration between the beginning and end of the draft as determined by the optical detector. The control calculates the length of the draft using the duration multiplied by the speed of the conveying surface.
Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.